Appleton™ Mercmaster™ III HID 50—250 Watt Luminaires

The Mercmaster™ III 50-250 Watt luminaire has a modular design that allows for scores of fixture component combinations to meet installation and lighting needs. The enclosed and gasketed construction allows it to fit a vast range of applications and is suitable for NEC and CEC Class I, Division 2/Zone 2; Class II, Division 1 and 2; Class III and other robust environments. Designed to dissipate heat from the ballast components out, Appleton’s thermal performance with the Mercmaster III leads the industry. Appleton’s heat reducing internal control design results in 18% cooler operation, which increases fixture durability and enables the Mercmaster III to be used in ambient temperatures up to +65°C (+149°F).


  • Typical applications include pulp and paper mills, processing plants, chemical plants, oil refineries, foundries, manufacturing plants, storage areas and marine applications
  • These medium base lamps accommodate 50 to 150 Watt high pressure sodium (HPS) or 175 and 250 Watt pulse start metal halide (PSMH) lamps. There is a wide range of voltages and ballast types available
  • A choice of heat-resistant prismatic glass refractors (NEMA II or V) or heat-resistant globes are available. They thread directly into the ballast housing and seals against a high-temperature silicone rubber gasket
  • Modular design allows scores of fixture component combinations to meet installation and lighting needs. Mounting hoods include cone-shaped pendant, standard pendant, flexible pendant, ceiling and wall (tapped for 3/4″ or 1″ NPT), 25° angle stanchion
  • Reflector choice includes standard dome and 30° angle types, both made of fiberglass reinforced white polyester; highly resistant to unusually corrosive applications. Reflectors are vented for cooler, dirt-free operation and maintained lumen output.
  • Hinge has high lip for added safety during installation and servicing. Hinge and bolt construction assures 360° compression at all points on ballast housing gasket for positive sealing. Swing-away design of captive bolt and nut simplifies servicing
  • Body gaskets and globe gaskets are high-temperature silicone rubber
  • All Mercmaster III mounting hoods have provision for easy field installation of fuses in fixtures (see fuse kit listings on catalog pages)
  • Guards are available to protect globes from damage. Keyhole slots allow easy installation and are secured with stainless steel screws
  • Restricted breathing (AEx nR) and restricted breathing/nonsparking (AEx nA nR) options are available making the Mercmaster III an ideal HID luminaire for use in Zone 2 locations
  • For electrical protection, a ground wire is provided on each Mercmaster to bond hood and ballast housing


NEC/CEC Certifications and Compliances
Class I, Division 2, Groups A, B, C, D; Class I, Zone 2, AEx nA nR IIC (Z2); Class I, Zone 2, AEx nR IIC (ZB); Class II, Division 1 and 2, Groups E, F, G; Class III; Type 4X; IP66; Simultaneous Exposure (Class I, Division 2/Class II, Division 1); Fixture
Specific Wattages
50 W HPS (MT – Voltage Only); 70 W, 100 W, 150 W HPS; 175 W, 250 W PSMH
Ambient Temperature
+40 °C to +65 °C (+104 °F to +149 °F)
120, 60 Hz; 120, 50 Hz; 120/208/240/277, 60 Hz; 120/208/240/ 277/480, 60 Hz; 220, 60 Hz; 225, 50 Hz; 230, 60 Hz; 240, 50 Hz; 240, 60 Hz; or 480, 60 Hz
Standard Materials and Finishes
Mounting hoods, bodies and guards are cast copperfree (4/10 of 1% max.) aluminum with electrostatically applied baked gray epoxy-clad finish. Globes are heat-resistant prismatic glass; reflectors are FRP with a polyester finish. Hardware, catch assemblie
Optional Fuse Kits
Fuses can be field-installed. Kits include fuse block, wire connectors and screws for attaching to mounting hood. Fixtures with fuses do not comply with Marine Type Electric Fixtures Outside Type (Salt Water) requirements for marine listing
Optional Photocell
A photocell to provide automatic on-off control is available as an option for all fixtures except those with cone or ceiling mounts
Glodok Exproof Product